Purpose: To present the importance of stress echocardiography indiagnosis of low flow-low gradient aortic stenosis (AS). Materialand Method: Two patients were tested, one male patient, aged 62,weight 72 kg, height 172cm, and BSA 1,86cm2, and the other one was female,aged 59, weight 83 kg, height 168 cm and BSA, were found to have at leastmoderate ASs with low flow and low gradients at rest. Dobutamine stresstest was performed using standard protocol starting at 2,5mcg/kg/min atrest as continuous infusion and increasing every five minutes intervals withstepwise increase up to 20mcg/kg/min. Monitoring with 12-lead ECG andblood pressure measurements at each step was performed. After completingthe test, transthoracıc echocardiography (TTE) showed in male patientincreasing in transvalvular flow and gradients across aortıc valve and ejectionfraction (EF) measured by Simpson method increased from 33% at rest upto 40% following Dobutamine administration. EOA (effective aortic valvearea) from 0,8cm2 at rest increased insignificantly to 0.85 cm, (0,425m˛)afterwards. Conclusion: Final diagnosis therefore was severe aortic stenosiswith preserved contractile reserve. The patient was scheduled for surgicalvalve replacement. In female patient after DST, the area of aortic valveincreased significantly from 0,75cm˛ up to 1,05cm˛, while all transvalvulargradients remained almost unchanged. Pseudo-Aortic Stenosis and surgicalvalve replacement had not been indicated at this time.
Key words: Aorticstenosis, Stress echocardiography
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